A nummus of the type that weighed 1/132 of a pound. It is one of 12 similar coins from the Seaton Down Hoard made around AD 330-335 in Siscia (now Sisak), modern Croatia, and issued by the House of Constantine.
It is a commemorative issue coin celebrating the foundation of Constantine I’s brand new capital of the Eastern half of the Empire, with Rome remaining the capital of the West. Constantinopolis later became Byzantium and is now Istanbul in modern Turkey. The front of the coin depicts the personification of Constantinopolis. The image on the reverse depicts Victory, a very common image on coinage, as a symbol of military success. She is easily identifiable by her wings.
This object is on display at RAMM in the Making History gallery.